Comtrol Modbus TCP User Guide - Manual (Page 69)

DeviceMaster UP Modbus/TCP User Guide: 2000447 Rev. I Chapter 4. Diagnostic and Statistics Pages - 69
PLC Interface Diagnostics
Slave Mode Specific Statistics
Messages Received From PLC
Displays the total number of raw data and Modbus RTU/ASCII
messages received from the PLC.
Responses Sent to PLC
Displays the total number of raw data and Modbus RTU/ASCII
responses sent to the PLC.
Raw Serial Port Data Messages
Received From PLC
Displays the number of serial port raw data messages received.
Raw Socket Port Data Messages
Received From PLC
Displays the number of socket port raw data messages received.
Modbus RTU/ASCII Messages
Received From PLC Displays the number of Modbus RTU/ASCII device specific messages
received.
Modbus RTU/ASCII Broadcasts
Received From PLC Displays the number of Modbus RTU/ASCII broadcast messages
received.
Invalid Command Lengths
Displays the number of messages received with invalid command
lengths.
Invalid Message Data Errors
Displays the number of messages received with invalid message data
errors. These errors occur when the DeviceMaster UP receives a
message that cannot be processed due to improper message data.
Unknown Request Destination IDs
Displays the number of messages received with unknown request
destination IDs.
Invalid Request Protocol Types
Displays the number of messages received with invalid protocol errors.
This occurs when a message is received with a protocol other than the
Modbus protocol value of zero.
Unsupported Modbus Function
Codes Displays the number of messages received with unsupported function
codes.
Master Mode Specific Statistics
Messages Sent To PLC Displays the total number of raw data messages sent to the PLC.
Responses Received From
PLC
Displays the total number of raw data responses received from the PLC.
Invalid Response Data
Errors
Displays the number of response data errors to polling requests returned from
the PLC. Possible causes include:
• Incorrectly formed transmit data memory format. (Possibly missing the
sequence number and/or length fields.)
• More data to transmit indicated via the length field than was returned in
the message.
• Transmit sequence number error. Sequence number increased by more
than one. This could indicate an unsent transmit message.
• Insufficient polling length configuration. (DeviceMaster UP polling length
is to small.)
• Attempting to transmit to large of message for a single Modbus/TCP
message. (More than 246 bytes of data.)